How vital is it for the UK to maintain the absolute right to exit the Customs Union? As pro-Brexit MPs have their political will tested to destruction, this question has become the fulcrum of the UK’s attempt to exit the EU.

The answer lies in a painstaking assessment of the UK’s trading performance within the EU. Using Office of National Statistics Data,Part 1 of my analysis showed how the Customs Union accounts for easily the worst-performing element of UK trade.Part 2 analysed the cost — in particular to the UK’s car producers and food consumers. Here I put the UK’s performance inside the Customs Union into global perspective. With multiple, 20-year comparisons — in US–EU trade, intra-EU trade, UK productivity and EU growth — this analysis reveals that the UK’s track record inside the Customs Union has been uniquely poor, by every reasonable measure or comparison. (All data used here is presented and sourced in: UK Trade: Goods & ServicesandUK’s Top 10 Sectors. Readers are invited to peruse both.)

The UK’s stagnant exports: What’s not to blame

The UK’s poor EU goods-export performance – a growth rate of just 0.22% per year since 1998 – is often attributed to the EU’s own flaccid economic growth. As a root cause, however, this is easy to eliminate by making two comparisons: first by measuring the UK’s performance inside the Customs Union against the exporting prowess of multiple non-EU countries; and second, by analysing how our EU partners have fared with each other over a similar period.

First, the track record of non-EU countries. In April 2017, Michael Burrage compared the growth rate of the UK’s goods exports into the EU with the growth rates achieved by multiple non-EU countries in It’s Quite OK to Walk Away. Using seven international trade databases, Burrage calculated that the growth rate of UK goods exports traded tariff-free into the EU’s Single Market from 1993–2015 was lower than for 35 other countries, many trading under Word Trade Organisation (WTO) terms. In no particular order, the countries that outperformed the UK included: Canada, the United States, Singapore, Brazil, Switzerland, India, Bangladesh, and – just– Australia.

Of the major global economies, only Japan has performed worse.

Second, the record of the UK’s own partners within the EU. What should deeply worry Customs Union supporters is that the UK’s performance inside the Customs Union is uniquely poor even by European standards. According toEurostat data, the UK’s goods export/import ratio (expressed as a percentage) within the EU has plummeted from 80% in 2003 to just 63% in 2017, far below Germany (now at 124%), France (86%), Italy (112%), Netherlands (113%), and Spain (91%). Incidentally, Ireland’s export–import ration with the EU stands at an impressive 155%.

As shown inPart 1, the UK’s services exports to the EU do not and cannot redress the UK’s resulting trade-in-goods deficit, so long as the UK stays in the Customs Union.

What these comparisons reveal is that the UK’s goods-export performance with the EU since 1998 is uniquely poor, even though the UK’s EU-bound goods exports is precisely the sector the Customs Union is supposed to promote. The UK’s failure cannot be attributed to the EU’s own poor economic performance, since virtually every other major economy in the world has performed better over the past 20 years whether they happen to have been a member of the Customs Union or not. Suppose, then, the UK has just been uniquely unlucky in the range of goods it exports to the EU? Suppose the types of goods the UK makes are flukishly unsuited to the terms of the Customs Union and the tastes of Europe’s consumers?

Uncle Sam thrashes the UK in Europe

Fortunately, we can test this assertion too, because the United States’ own trade with the EU presents an almost heaven-sent comparison. The reason is the near equivalence in the value of the UK’s and US’s goods exports to EU back in 1998, and a startlingly similar range of export products – from aerospace goods and motorbikes to construction-site diggers and whisky.

Back in 1998, US goods exports to the EU were fractionally lower than the UK’s: £91.7 bn to the UK’s £99.9 bn at the prevailing exchange rate (UK Trade: Goods & Services, Tab 3, Section 10). But since then – more precisely, since 2008 – US goods exports have grown far more quickly. Over the entire, two-decade period, US goods exports to the EU have grown at a compound annual growth rate (CAGR) of 2.11% per year — as opposed to the UK’s 0.22% per year (Section 9).

The result: after 20 years of not being in the Customs Union, nor having a bilateral trade agreement with the EU, nor participating in Single Market rules, the US has comprehensively outstripped the UK as a goods exporter to the EU, with exports worth £219.8 bn in 2017 as opposed to the UK’s £164 bn. From near parity in 1998, US goods exports to the EU have grown almost 2% faster per year than the UK’s and are now 35% more valuable. As far as any analysis ever can, this dramatic divergence in export performance proves that seamless, tariff-free trade with the EU is absolutely not vital to exporters.

So, what is going on? Economists may one day discover that the Customs Union has been positively deleterious to UK producers as opposed to plain unhelpful. For what it’s worth, this author observes that Customs Union confers no commercial advantage in sectors where the UK is highly competitive (aerospace, defence, jet engines, pharmaceuticals), and gives EU companies preferential access where the UK typically isn’t (mass-market cars, food, agriculture, machinery). And where the Customs Union provides no advantage, EU customers often procure US goods: EU airlines’ general preference for US-made turbo-jet engines would be a good example (UK’s Top 10 Sectors, Tab 2 (Transport), Section 5).

Nevertheless, the immediate issue is practical: Is the UK’s experience inside the Customs Union sufficiently bad that the absolute right to exit is worth the risks of a unilateral exit from negotiations and trading with the EU on WTO terms? In the global scale of poor trade relationships, does the end result of the UK’s experience in the Customs Union – a steadily deteriorating £95 trade deficit – really matter?

The £95 billion warning sign

The most logical comparison is, again, with the United States. That country, too, runs huge trade deficits in goods, which are partly redressed by surpluses in services. It’s biggest is the (2017) US$337 billion trade deficit with China. Highlighting this deficit formed a major element in Mr Trump’s campaign for the White House. US trade policy aims to reduce it.

So how does the scale of the UK’s deficit with the EU stack up with the US deficit with China? Are they of equal import? Or, to fashion the question more bluntly: should MPs worry that at some point, the UK’s £95 bn deficit with the EU will become an incendiary political issue all of its own?

If you convert the UK’s overall 2017 EU deficit into US dollars (goods plus services) at an exchange rate of $1.35 to £1, the resulting UK–EU deficit is $78.7 billion. But then the US economy is approximately 6‒7 times larger than the UK economy. Taking that into account, the UK has a deficit in comparative terms approximately 47% bigger than the US’s (Tab 3, Section 8).

More generously, you can translate the dollar trade deficit into a deficit per head of population, which gives a UK‒EU deficit of $1,216 per head, as opposed to a US‒China deficit of $1,050 per head. Calculated this way, the UK has a headache that is 16% more painful than the one that helped get Mr Trump elected.

Regardless of how adeptly the UK uses this deficit in future trade negotiations, it will, since it is deteriorating, eventually transmute into a political debate about the impact the Customs Union has on jobs. At that point, proponents of a new UK‒EU customs union – or indeed, any form of apparently seamless trade – are likely to hit extremely choppy political waters.

No, the Customs Union doesn’t create jobs

The reason for caution is the glaring discrepancy between the growth rates of exports and the UK’s own productivity growth rate (UK Trade: Goods & Services, Tab 3, Section 9). Observing that hundreds of thousands of jobs currently depend on trade with the EU is a quite different proposition to saying that membership of the Customs Union and Single Market has created jobs that otherwise wouldn’t exist — or that it isn’t steadily removing them.

The difficulty here is that the UK’s annual goods-export growth rate to EU (0.22%) is far lower than those other metrics which economists would normally expect it to exceed. It is just one-tenth of the UK’s average 1998–2017 GDP growth rate (2%, according to ONS). It is also slower that the Eurozone’s own growth rate, of 1.56% per year (calculated from 1995 – 2018, Section 5).

But the UK’s goods-export growth to EU is also far slower than the UK’s productivity growth rate over the same period ‒ 1.19%, according to ONS ‒ which is the rate at which UK companies and organisations become more efficient each year. This means it is statistically impossible for there to be more people engaged in EU goods-export activities in 2017 than in 1998. Which means, in turn, that the Customs Union cannot – net – have added a single job to the UK economy since 1998. Statistically, there have to be fewer jobs (as measured in value) involved in exporting goods to the EU in 2017 as compared to 1998 — despite the Customs Union.

In contrast, the growth in the UK’s EU trade deficit from -£5.6 bn in 1998 to -£95 in 2017 denotes the creation of hundreds of thousands of jobs in other EU countries, to supply goods to UK markets. This author roughly estimates the number created in EU to supply the UK’s motor market alone since 1998 at just over 40,000 (see Part 2). It is clear that continental Europe benefits greatly from keeping the UK in the Customs Union. What the UK gets out of it is – statistically – a mystery.

Summary – The Customs Union fails to deliver

So: if the Customs Union and Single Market have gently throttled UK export growth over 20 years; if they deliver crushing deficits that the UK’s non-EU trade then has to pay for; if their quality of seamlessness lies principally in helping investment slide overseas; if they force-feed UK households on the most expensive food on earth while offering no reciprocal advantage to any sector of UK trade except financial services, and then only in a limited way; if the reason for stagnant exports can’t easily be attributed to anything other than the Customs Union and Single Market themselves; and if the end result is a deficit 16% worse than the one that helped gain the Presidency for Mr Trump, then the UK’s strategic interest should be crystal clear.

Whatever its theoretical benefits, it has proven to be the wrong customs union for the UK since 1998. It delivers no commercial benefit to the UK’s fastest-growing manufacturing sectors (pharmaceuticals and aerospace); and leaves all the UK’s other major goods-export sectors in a state of either stagnant growth, huge deficits, or both. By any reasonable comparative measure the UK’s performance inside the Customs Union since 1998 is the picture of a failed trading relationship. And yet clinging to that failed relationship may now prevent the UK from liberalising trade with export markets that have grown quickly during the past 20 years – markets that are receptive to UK goods; markets that actually create jobs.

If the price of the UK’s exit from the EU is remaining in the Customs Union, then the cost will be paid by the UK’s manufacturing industry. That’s the lesson of the past 20 years.